Generate survival times according to hazard rate
\(h(t) \exp(\mu)\) with \(h(t)\) the hazard rate associated with the
specified inverse cumulative hazard rate invchaz and \(\mu\) the
specified true hazard ratio mu. See Bender et al. (2005).
Usage
gen_surv_times(invchaz, mu = log(1), data, coxphmod = NULL)
Value
A vector of survival times from subject entry time.
Arguments
invchaz
the inverse cumulative (baseline) hazard rate to be used
for generating survival times. Must take vector inputs!
mu
the true hazard ratio used to generate survival times.
data
an integer number of survival times to generate or
(in combination with coxphmod): a data.frame containing
subject covariates in named columns.
coxphmod
(optional) a cox proportional hazards regression model as produced by
the function coxph(). Standard practice: coxph(Surv(survtime, censorid) ~ covariates, data = data).
Alternatively, a list with:
$formula (~ covariates)
$coefficients (named vector specifying risk adjustment coefficients
for covariates - names must be the same as in $formula and colnames of data).
Author
Daniel Gomon
Details
Sometimes it is desirable to generate survival times from an
increased hazard rate $$h(t, \mu) = h_0(t) e^\mu$$
with \(h_0\) the baseline hazard rate. We call \(e^\mu\) the true hazard ratio.
References
Bender, R., Augustin, T., & Blettner, M. (2005).
Generating survival times to simulate Cox proportional hazards models.
Statistics in Medicine, 24(11), 1713-1723. tools:::Rd_expr_doi("10.1002/sim.2059")